Mix the cornstarch with enough water to make a thin paste.,______,Remove mushrooms and set aside.,Add 1 tbsp soya sauce and 1 tbsp chicken broth to the pan juices and add chicken, turning to coat as much of the chicken as possible in the soya sauce.,Cook at a medium low heat until the chicken is almost done.,Mix the remaining chicken broth and 1/2 c water (or broth) in a saucepan.,Bring to a boil.,Add a few tbsp of the hot liquid to the cornstarch paste, stir until smooth and then stir into the boiling gravy until thickened.,Add the mushrooms and green onions to the gravy.,Stir to mix.,Salt and pepper to taste.,Pour gravy over chicken in pan and simmer until fork tender.